Tidal spirometric curves obtained from a nasal cannula.

Area of Science:

• Pulmonary Medicine
• Biomedical Engineering
• Medical Devices

Background:

• Spirometry is the standard for assessing lung function but has limitations like requiring forced exhalation and providing only snapshot data.
• Existing alternative methods like pneumotachography and plethysmography are complex or sensitive to movement.
• There is a need for an easy-to-use, accurate method for frequent or continuous monitoring of tidal breathing.

Purpose of the Study:

• To develop and validate a novel, user-friendly method for assessing lung function using nasal cannula pressure recordings.
• To enable continuous or frequent monitoring of tidal breathing patterns for improved respiratory diagnostics.

Main Methods:

• Developed an algorithm to convert nasal cannula pressure recordings into scaled flow-volume curves with self-calibration.
• Validated the method using 3D-printed infant and adult upper airway models with realistic breathing patterns.
• Compared pressure-derived flow-volume curves against imposed flow-volume curves for accuracy assessment.

Main Results:

• The algorithm accurately converts nasal cannula pressure into scaled flow-volume curves.
• Validation demonstrated a very high level of accuracy in healthy and unhealthy breathing patterns.
• The method proved effective in anatomically correct 3D-printed airway models.

Conclusions:

• Nasal cannula pressure monitoring offers a promising, accurate, and easy-to-use approach for assessing lung function.
• This technology facilitates remote monitoring of patients with chronic lung diseases.
• The self-calibrating algorithm enhances the reliability and applicability of the method for continuous breathing assessment.